Sound box for talking machines



A. H. GAY.

SOUND BOX FOR TALKING MACHINES. APPLICATION FILED APR. 20. 1921.

Patented May 30; 1922.

28 l i 15 IEIILLZ 18 6 'Fig. 6'. 2 0 21 STATE-S TENT orr ca.

HALBERT HARDY GAY, or LONDON, ENGLAND,

sounn BOX iron TALKING MACHINES.

iaiaeae. l i

To all whom it'ma i concern: 1 v

Be it known that I, Anniiirr HARDY-GAY, a subject of the' King of GreatBritain and Ireland, residing at London, England, have invented certainnew and useful Improvements in SoundBoXes for Talking Machines, of whichthe following is a specification. I

This invention relates to sound boxes for talking machines and has forits object to increase the volume of the reproduction, and to obtain areproduction more closely approaching the originahas regai-dstone andarticulation. it

, The invention has also for its Ol)]60l3 to reduce to the minimum thehissing, and other undesirable surface noises incidental to talkingmachines and the like sound reproduc ing instruments. Y I r r Theinvention cons sts in the features of construction combination andarrangement of parts, hereinafter more fully described with reference tothe accompanying drawings and claimed in the appended claim.

' In the drawings wherein like reference numerals are employed toindicate corresponding parts in the variousfigures Figure 1 is a--sectiona1fside elevation of the complete sound box. I V

Figure 2 a front elevation corresponding to Figure 1, but with the cap22 removed.

Figure ,3 is a sectional-side elevation correspondin'gto Figure 1 butturned through an angle of 90. I

Figure 1 is a front elevation looking in the direction of the arrow inFigure 3.

, Figure 5 is a sectional side elevation showing modified connectingmeans for the tone arm, and

Figure 6 is an enlarged detail view showing more clearly the means forinsulating the stylus bar and bracket for the fulcrum pin, from saidfulcrum pin.

Referring to the drawings, an open ended circular casing 1 of metal suchas brass or aluminium forming the sound box proper, and somewhat deeperthan the usual soundboX, is reduced circumferentially at one endhereinafter referred to as the back end, to form a shoulder 2, and hasan inwardly projecting flange 3 extending from such reduced end.

Two rings a, 4, of hollow formation and constructed of rubber are fittedin the casing 1, and are adapted to receive between them the diaphragm5, at its edge.

A cover 6 is screwedon the other end of Specification of Letters Eatent.Pat nt d pl 30 1922 i ;App'1ieation fi1ed April 20, 1921. Serial No.462,817. I 1

. the casing 1, herein'after referred to as the frontend, and serves toretain the rings 4 in position between it and the inwardly proectingflange 3, thefdiaphragm 5 being thereby clamped between the rings 4:. 1.

This front cover 6 has a central outwardly extending boss 7, formed witha bore 8 of tapered Or flared form, the wider end openin g directly intothe casing 1, opposite to the diaphragm 5. I I I I It is preferred toform this bore, with curved wallsin cross section as shown so as toproduce as it were a trumpet mouth.

A ring of fibre 9 is screwed on the boss 7, at its outer end, such ring9 being insulated from the boss by a ring of rubber 10 which isinterposed between the facing surfaces.

The fibre ring 9 is of somewhat less on ternal'diameter and of somewhatgreater iiiternal diameter than the corresponding diameters of the boss7, and issecured on'the boss 7, concentrically therewith.

slipped on to the fibrering 9 so that its outer surface is flushwith'the outer surface of the boss 7 and rubber ring 10, and'an innermetal ring 12, preferably aluminiumis fitted in the fibre ring 9, thebores of the rubber and inner rings lOand 12 forming a continuation ofthe bore 8 of the boss 7 but with parallel walls. i

The various rings may be secured in position in any suitable manner forexample by frictional engagement: alone or by screws,

The casing 1 has secured on its circumference a bifurcated bracket 13 toreceive the fulcrum pin 14 for the stylus bar 15, which is secured tothe diaphragm 5 in the usual manner at one end and is bent and enlargedsomewhat at the other end, as shown at 16 which is to be pivoted in thebracket 13.

In order to prevent direct metallic contact between the stylus bar 15and its fulcrum pin bifurcated bracket 13 to receive the fulcrum pin 1e,are fitted with fibre bushes 17 and the aperture in the stylus bar 15through 14 the apertures provided in the fulcrum pin 14, is passedthrough the limbs of the inverted U-shaped insulator 19.

The stylus bar '15 is provided at its free end with a socket 20 toreceive the needle,

such socket 20 having a set screw 21 for clamping the needle inposition.

'The circumferentially reduced end of the casing is adapted to receive ahollow cap 22 constructed of wood, the edge of the cap 22 bearingagainst the shoulder 2 formed on the casing 1 by reducing the diameterthereof as! hereinbefore" described. a

The cap 22 is reduced in diameter inter nally for ashort distanceinwardly to form a rabbeted joint 23, and is provided with an aperture24: in its wall, to allow the stylus bar 15 to pass therethrough.

In order to enable thesound box to be connected to the tone arm, whichis of the well. known form and therefore does not require to bedescribed or' shown, two studs 25 are secured indiametrically oppositepositions,

-- on thering 11, forengagement in the usual slotsin the tone arm. v

These studs 25 as shown more clearly in Figure 3 consist of shortlengths of tube surrounding screws 26 which pass through the ring 11into the fibre ring9.

Alternatively: and as illustrated by Figure, 5 the fibre ring 9 may haveformed therein in diametrically opposed positions two cavities 27 inwhich. are arranged springs28 adapted to bear on balls 29 fitted insockets 30 formed inthe; ring 11, the sockets being such as to permitthe balls to be projected outwardly by the springs beyond theperipheryof thering 11 but to prevent them passing entirely through thering 11;

The balls 29 are adapted in the connected position of the sound boxandtone arm to engage in sockets in the form of apertures 31 in the wallof acircular casing 32 provided at the end of a tone arm 33, which ishere shown broken away as the only unusual feature is the addition ofthe'casing 32. This'45 casing 32 is provided internally with acircumferential groove 34 which connects the apertures 31. A

By means of this connection the sound box can be rotated or swung roundrelatively to the casing 32, to facilitate insertion of the usualplaying needle,- in its socket 20, the v balls 29 being pressed inwardlyagainst the action of their springs 28, and running in the groove 34,When the needle has been inserted in its socket20, "the sound box isrotated in the opposite direction, the balls 29 again running in thegroove 34 until they is of increased volume, and is practically 2 freefrom the undesirable hissing andother surface noises incidental totalking machines,

I clalmz A sound box fortalking machines having a bifurcated stylus barbracket, a fulcrum pin mounted in the respective arms of the bracket, astylusbar mounted on the pin be tween the arms of the bracket, a stripmounted on the pin on oppositesides of the'stylus bar mounting andserving to maintain said stylus bar mounting in a predetermined positionlongitudinally of the p-inand spaced from the arms of the bracket, andan insulating section arranged between the pin and 1 the stylus barmoiuiting, I,

In testimony whereof I have signed my name to this specification. e

F ALBERT HARDY- GAY. i

